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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Thomas<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Hoopl works on control flow graphs, whereas Core is lambda calculus. I really don’t think Hoopl is going to be any good for optimising
Core.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Ask the ghc-devs mailing list too. Someone there has been writing about arrows recently (take a look at the archive).<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Simon<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Thomas Bereknyei [mailto:tomberek@gmail.com]
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<b>Sent:</b> 02 March 2015 17:07<br>
<b>To:</b> nr@cs.tufts.edu; Simon Peyton Jones<br>
<b>Subject:</b> Hoopl and Arrows<o:p></o:p></span></p>
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I've been interested in Arrows and their optimization recently. I've run into problems during basic tooling so I built a quasiquoter for proc notation (still working on rec and let statements, but the rest of it works) that converts from haskell-src-exts into
a desugarred TH format. My original goal was to implement "Casual Commutative Arrows" [1] but to make it more user friendly and to include arrows with effects. I came across Hoopl and at first glance I would think it can help with Arrow optimization, especially
with the tuple shuffling from desuggared proc-do notation. In spite of the slogan of "Hoopl: Dataflow Optimization made Simple" and the git repo's testing folder, I'm not 100% clear on Hoopl usage. I would be interested in anything that can get me started
or even a thought or two whether it would be worth looking into for Arrows.<o:p></o:p></p>
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Simon, regarding [2], my quasiquoter can be rewritten to take `bind`, `bind_`, `fixA`, and `ifThenElseA` from scope rather than being built in. Would that help with #7828? I am not very familiar with GHC internals at the moment, and I am confused about the
complexity of dsArrows.hs in contrast with my own parser. It seems I have a good start on it in the Parser module at [3], WARNING: untested and rough draft code, though suggestions and pointers are welcome. I was thinking of sending some of my code to haskell-src-meta
because they can't yet translate their version of Exp into TH's ExpQ.<o:p></o:p></p>
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-Tom<o:p></o:p></p>
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[1] (<a href="https://hackage.haskell.org/package/CCA">https://hackage.haskell.org/package/CCA</a>)<br>
[2] (<a href="https://ghc.haskell.org/trac/ghc/ticket/7828#comment:54">https://ghc.haskell.org/trac/ghc/ticket/7828#comment:54</a>)<br>
[3] (<a href="https://www.fpcomplete.com/user/tomberek/rulestesting">https://www.fpcomplete.com/user/tomberek/rulestesting</a>)<o:p></o:p></p>
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